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        <td class="header">&nbsp; Wave Mode Polar View</td>
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<h3>ASAR Wave Mode Products</h3>

<p>The ENVISAT ASAR sensor in Wave Mode acquires small imagettes (5 km by 5 km to 10 km
    by 5 km size, high-resolution complex images of ocean scenes), allowing data
    acquisition to occur periodically (every 100km) around a full orbit. This
    constitutes the level 0 product, which is systematically produced for all data
    acquired within this mode<span style="font-size: 12pt; font-family: &quot;Times New Roman&quot;;"
                                   lang="EN-GB">.</span> &nbsp;</p>

<p><span lang="EN-GB">These are processed to derive the spectra of the surface
backscatter, and consequently the wavelength and the direction of the ocean
waves.</span></p>

<p><br>ENVISAT ASAR has two level 1 products and one level 2 product:</p>

<div style="margin-left: 40px;"><p><strong>ASA_WVI_1P</strong>: The product can contain up to 400 SLC
    imagettes, each 10 km x 10 km in size, which are acquired every 100 km.
    The imagettes are 1 look in azimuth and 1 look in range. The WVI product also contains the Cross Spectra of the
    imagettes.<br><br><strong>ASA_WVS_1P</strong>: This product contains the Cross Spectra of the
    imagettes.<br><br><strong>ASA_WVW_2P</strong>: This product contains the Wave Spectra.</p></div>
<br>

<p>
    The Cross Spectra is a polar grid of complex data with 24 bins in wavelength and 36 bins in direction&nbsp;(each 10
    degrees
    wide).</p><br>

<div style="text-align: center;"><img style="width: 608px; height: 691px;" alt="" src="images/cross_spectra.jpg"><br>
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<br><br><h4><a name="productView">Polar View</a></h4>

<br>

<p>
    The Polar View is used for displaying Cross Spectra and Wave Spectra from ENVISAT ASAR Wave mode products.<br><br>The
    Polar View shows one record at a time. You may use the buttons and
    slider at the bottom of the view to change the currently viewed record.
    The Animate button allows the view to cycle through records
    automatically.<br><br>Readouts for Peak Direction and Wavelength,
    Min/Max Spectrum and Wind Speed and Direction can be viewed on the
    right hand side of the polar plot.<br><br>Cursor readouts for
    Wavelength, Direction and Value can be viewed on the left hand side of
    the polar plot as you move your mouse over each bin.</p><br>

<div style="text-align: center;"><img style="width: 780px; height: 623px;" alt="" src="images/polarView.png"><br>
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<p class="MsoNormal">For more information on ASAR Wave mode
    products: </p>


<p class="MsoNormal">ASAR Product Handbook &#8211; Chapter 2 -
    ASAR Products and Algorithms</p>

<p class="MsoNormal"><a href="http://envisat.esa.int/handbooks/asar/CNTR2-6.htm#eph.asar.prodalg.levb">http://envisat.esa.int/handbooks/asar/CNTR2-6.htm#eph.asar.prodalg.levb</a><span
        lang="EN-GB"></span></p>
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